🎨 Palette: Improve node_modules empty state

[acebytes]

💡 What: Replaced the plain text "No node_modules directories found" with a structured empty state containing a relevant SF Symbol (shippingbox) and appropriately styled text (.callout / .secondary).

🎯 Why: Users can misinterpret an empty dynamic list as a broken UI or frozen app. A structured empty state with visual feedback indicates the list is intentionally empty, aligning with other empty states in the application.

📸 Before/After: N/A

♿ Accessibility: Added a clear visual structure for the empty state making it easily identifiable.

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PR created automatically by Jules for task 16969584701515621322 started by @acebytes

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